Supporting mechanism for the crown sheave of a drilling machine



J. A. ELM E5 June 21, 1938.

SUPPORTING MECHANISM FOR THE CROWN SHEAVE OF A DRILLING MACHINE Filed April 16, 1937 2 Sheets-Sheet l June 21, 1938. A, s' 2,121,078

SUPPORTING MECHANISM FOR THE CROWN SHEAVE OF A DRILLING MACHINE Filed April 16, 1937 2 Sheets-Sheet 2 a2 65 62 66 I 7g 63 I 69 J 68 6'? W Patented June 21, 1938 UNITED STATES PATENT OFFICE Keystone Driller Company, Beaver Falls, Pa., a corporation of Pennsylvania Application April 16, 1937, Serial No. 137,298

Claims.

This invention relates to a supporting mechanism for the slide at the top of a derrick of a drilling machine which carries the crown sheave and over which the line passes which carries and reciprocates the drill used in drilling operations.

It has heretofore been the practice to mount the crown sheave slide in such manner that it is vertically slidable longitudinally of the derr'ick or mast and supported by heavy compr ssio springs which com ress "on reciprocating the drill up- Wardly and reduce the amount of vibration of the machine during drillihg operat'ion. However, especially when a steel drill line was employed, the dropping of the drill caused the drill to bounce, creating slack in the drill line immediately taken up by the springs supporting the crown sheave slide. Subsequent to this bounce of "the drill the drill line was placed under tension by the spudder mechanism, this effecting "a jerk on the drill line again compressing the springs supporting the slide. This action known as a double shu'iile, is highly undesirable in a drilling machine as it creates excessive vibration, loosening the partsbf the drilling machine and impairing its efficiency. Where a hemp drill line was employed this effect was not so pronounced as the hemp linejwouldstreteh considerably and avoid destructive vibrations. With the employ: ment of steel cable as the drill lines the effect of this double'shufiie was intensified and became extremely destructive to the machine. .[t is the principal object ot the invention to provide a means for retarding the upward movement of the crown sheave slide "by its sup orting spring, particularly at the time following the strike of the drill, thereby to reduce the double Jierk created by the bouncing of the drill.

Another object of the invention is to provide such retarding means which 'is in the form of a "hydraulic shock absorber "and is mounted at the upper end of the mast or derrick close to the crown sheave slide.

Another object 'of the invention is to provide such a retarding device which is adapted to be mounted on the upper section of a telescopic derrick, the invention including one form in which the shock absorber islocate'd outside of the derrick and above that portion of the upper section telescoping into the lower section and including another form in which the shock absorbing device is housed within the derrick itself. By this means the shock absorber does not interfere with the telescoping of the derrick.

Other objects of the invention are to provide such a retarding mechanism for the crown sheave slidewhich is compact in construction and will readily dissipate the heat generated, and will stand up under conditions of constant use without impairment of efilciency.

In the accompanying drawings:

Fig. 1 is a fragmentary side elevation of a drilling machine having the action of its crown sheave slide retarded by a mechanism constructed in accordance with my invention.

Fig. 2 is an enlarged fragmentary rear elevation of the upper end of the telescoping derrick shown in Fig. 1. a

Fig. 3 is a Vertical section, taken on line 3-3, Fig. 1.

Fig. 4 is a fragmentary vertical section, taken on line 4 4, Fig. 2, and

Fig. 5 is a View siinilar to Fig. 4, showing a modified form of myinve'ntion.

The retarding mechanism forming the subject of my invention maybe used in connection with a driller of the crawler type, as shown, or with any other type of either fixed or portable driller having a telescoping derrick or mast which carries a crown sheave. The frame and reciprocating mechanism of the driller can be of any suitable 25 construction andis illustrated in fragmentary 'form,-reference being made'to my co-pending application $91. No. 120,422, filed January 13, 1937, entitled Tool guides for drilling machines, for a more detailed showing of these features.

The driller shown comprises a frame indicated generally at H) suitably supported on crawlers indicated generally at II and carrying an internal combustion motor (not shown) which propels the driller and also furnishes power for the operation of the tools. The frame H) includes the usual main sills I3, front posts. l4 carrying walking beam guides l5, and braces f6. i

The telescoping derrick or mast, indicated gen erally at H, is composed of a loWersection l8 into which the upper section I9 is adapted to telescope. The lower section I8 is supported on the carriage ll] of the driller and is preferably capable of being laid back for convenience in transporting the driller, being supported for this purpose by a pivot shaft 20 suitably secured to the 'derri'c'k and braced by braces 2| and journaled in bearings 22 at the upper ends of the front pOsts'l-l of the frame. The lower section l8 of the derrick is preferably of the latticed ladder type, being composed of spaced steel channels 23 connected by welded horizontal and diagonal braces (not shown), the upper ends of thechan- -ne1s 23 being connected by cross bars '24. The upper telescoping section I 9 of the derrickis likewise shown as being made of the latticed ladder type, having two spaced channels 26, 21 connected by welded horizontal and diagonal braces 28 and connected at their upper and lower ends, respectively, by channels 29 and 36. The upper section I9 is telescopically received in the lower section l8 of the derrick and an elevating mechanism for the upper section I!) is provided. This elevating mechanism can be of any suitable form and is shown as comprising a series of sheaves carried by the upper end of the lower section l8 and the lower end of the upper section l9 and around which a cable 3| passes, the arrangement of sheaves being such that upon drawing the cable 3| downwardly the upper section 19 is extended. The derrick is shown as being braced by means of tubular braces, indicated at 32.

At its upper end the derrick carries the usual crown sheave 35 which is supported by a slide indicated generally at 36. The slide 36 can be of any suitable construction and is shown as including lateral extensions 31, 38 at its front and rear sides which engage and slide along the outer faces of the flanges of the channels 26 and 2'! of the upper derrick section. This slide carries a shaft 39 and the crown sheave 35 is preferably supported on the shaft 39 by means of an antifriction bearing 40.

The upper section of the derrick is also shown as carrying at its upper end the usual sand line sheave 45 which supports the sand line 46 used for lowering sand pumps or the like into the drill hole, the other end of this sand line being wound upon the usual sand reel (not shown).

The spudder mechanism for the driller includes a pair of walking beams 50 supported at their rear ends on the usual rear spudding shaft (not shown) and carrying at their front ends a front spudding shaft 5|. The walking beams are guided at their front ends by the walking beam guides I 5 and each end of the front spudding shaft 5| is connected by a pitman 52 with a crank 53, this crank being driven, under suitable control, to oscillate the walking beam assembly during the spudding operation. The line 54, usually a steel cable, from the crown sheave 35 passes under a sheave 55 slidingly mounted on the front spudding shaft 5| and is wound upon a drum 56 which is used to pay off the line 54 as the drilling progresses and is also used to hoist the drill. The drill 51 is carried at the free end of the line 54 and is shown as passing through a tool guide 58 forming the subject of my said copending application.

The downward movement of the slide 36 is limited by a pair of rests or stop plates 60 bolted to the front and rear sides of the channels of the upper derrick section and the slide is supported by an outer helical compression spring 6| and an inner helical compression spring 62. The lower ends of these springs are supported by a plate 63 which is mounted on a plurality of ears 64 welded to and projecting outwardly from the flanges of each of the side channels 26 and 21. These ears 64 are near the dividing line between the portion of the upper derrick section l9'which telescopes into the lower derrick section l8 and that portion of the upper derrick section l9 which does not telescope into the lower derrick section I8 and which carries the crown sheave and its spring support and retarding mechanism. This division of the upper section l9 into telescoping and non-telescoping sections is obtained by the provision of a pair of rests 59 which engage the upper ends of the channe s, Z3 01? the lower derrick section when the upper derrick section I9 is telescoped therein to the maximum extent; A vertical spring rod 65 is screwed into the lower end of the slide 36 and extends through a slideway 66 provided in the supporting plate 63. On the lower end of this rod 65 a nut 61 is provided, this nut supporting a washer 68 and a rubber cushioning disk 69. It will be seen that the rod 65 limits the upward movement of the slide 36 and that the rubber disk 69 cushions the impact of the rod 65.

Without the use of a device retarding the return movement of the springs BI and 62 a double jerk is imparted to the tool line 54 following the impact of the tool on the bottom of the drill hole. This double jerk is transmitted to the derrick and main frame of the driller and is extremely destructive in its effect. This double jerk is created by the bounce of the drill. When the drill bounces the resulting slack created in the tool line 54 is immediately taken up by the compression springs 6| and 62, these springs reacting to lift the slide 36 and crown sheave 35. Before load of the tool is again taken by the spudding mechanism the crank shaft 53 has passed beyond dead center and therefore the load of the tool is picked up by the spudding mechanism with a jerk which again compresses the springs BI and 62. It will be appreciated that this jerky effect due to the high speed of reaction of the springs GI and 62 sets up a pronounced vibration in the machine when the tool is being operated at a normal rate of, say, 60 reciprocations a minute.

To avoid such destructive vibration the present invention proposes to employ a shock absorber to retard the rebound of the springs 6| and 62. In the form of the invention shown in Figs. 1-4 an outboard shock absorber is provided and is mounted above the rests 59 so as not to interfere with the maximum telescoping of the section l9 into the section 23. For this purpose a bracket 10 is mounted on and projects laterally from the channel member 26 of the upper section l9 of the derrick above the rests 59 and hence on the non-telescoping portion of the derrick section IS. The shock absorber is mounted on this bracket 16 and is shown as comprising a cylinder 1| bolted thereto and having a cover 12. The piston of the shock absorber includes two vanes or wings 13 journaled to rotate about an axis concentric with the cylinder H in chambers 15 formed by radial partitions 16 in the cylinder. The cylinder Il may be grooved or cut away as indicated at 11 so as to provide a restricted tapering by-pass from one side of each piston vane I3 to the other and in addition bypass ports 18 under control of an adjusting screw or valve 19 extend from one side of each piston to the other, these by-passes and the adjusting screw providing an adjustment for the effect of the shock absorber. The shaft 80 of the piston may be formed integrally therewith and is shown as journaled in the cylinder H and cover 12 and to the outer end thereof is secured an arm 8| connected by a drag link 82 to the slide 36, the slide being provided with a boss 83 to which the upper end of the drag link 82 is pivotally secured, as indicated at 84. When the shock absorber is filled with a liquid the movement of the piston in either direction is resisted by the restricted by-passes 11 and 18, the shock absorber being of the double acting type.

With the provision of the shock absorber it will be seen that when the tool 51 bounces on striking the rock at the bottom of the hole the springs 61 and 62 are not permitted to rebound violently in taking up this slack but the rebound movement of these springs is cushioned by the shock absorber. By so cushioning the action of these springs the drill is thereafter picked up by the spudding mechanism without violence and in particular the double jerk created by the violent rebound of the unchecked springs BI and 62 is avoided.

Instead of the outboard shock absorber shown in Figs. 1-4 it is apparent that the shock absorber could be housed within the derrick and constructed of such form as not to interfere with the telescoping of the upper section it). Such'a shock absorber is illustrated in Fig. 5 in which the rod 65a, corresponding to the rod 65 in the preferred form, is extended downwardly to provide a piston rod moving axially in a vertical cylinder Bil. Suitable glands or stufiing boxes 9! and 92 are provided at each end of the cylinder around the piston rod 650. and a piston 93 is welded or otherwise suitably secured to the piston rod. This piston is provided with ports El i which are covered by a circular plate 95 resting on the upper face of the piston. This plate is free to slide relative to the piston rod and an annular shoulder 96 is provided on the piston rod for limiting the upward movement of the plate 95. With this construction the downward movement of the piston raises the plate 95 and permits the liquid contained in the cylinder to pass freely from the lower side of the piston to the upper side thereof. On the reverse movement, however, of the piston the plate 95 drops down to cover the ports 94 and hence the only flow of liquid from one side of the piston to the other is that which leaks past the plate 95, this being sufficiently restricted to properly cushion the rebound action of the springs 9! and 92. It will therefore be seen that the shock absorber shown in Fig. 5 is of the single acting type and it will also be appreciated that an adjustable by-pass could be provided from one side of the piston to the other to regulate the cushioning effect thereof. The shock absorber shown in Fig. 5 is made sufiiciently small so as not to interfere with the telescoping of the upper section I9 to the rests or ears 64.

From the foregoing it will be seen that both forms of my invention avoid the double jerk inherent to the use of a spring supported crown sheave in a driller employing a steel cable for supporting the drill and greatly reduces the destructive vibrations created by such springs in their rebound movement. Further, by mounting the shock absorber at the top of the derrick the assembly is rendered extremely compact and also by mounting the shock absorber in an outboard position above the telescoping portion of the upper derrick section, as shown in Figs. 1-4, or housed within the derrick, as shown in Fig. 5, the shock absorber does not interfere with the maximum telescoping of the upper derrick section. While I have shown a specific embodiment of my invention it will be appreciated that the invention is capable of wide modification and the invention is therefore not to be construed as limited to any particular construction but is to be iccorded the full range of equivalents comprehended by the following claims.

I claim as my invention:-

1. A drilling machine, comprising a frame carrying a spudder mechanism, a derrick rising from said frame, a vertically movable crown sheave slide at the upper end of said derrick, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and derrick and yieldingly supporting said slide in an elevated position, a hydraulic shock absorber mounted on said derrick and means operatively connecting said hydraulic shock absorber with said slide to retard the action of said spring.

2. A' drilling machine, comprising a frame carrying a spudder mechanism, a derrick rising from said frame, a vertically movable crown sheave slide at the upper end of said derrick, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and derrick and yieldingly supporting said slide in an elevated position, a hydraulic shock absorber including a liquid filled cylinder mounted on said derrick below said slide, a piston in said cylinder and a connecting member extending downwardly from said slide and operatively connected at its lower end to said piston, said hydraulic shock absorber retarding the action of said spring.

3. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and an upper section having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, a hydraulic shock absorber mounted on said upper derrick section and means operatively connecting said shock absorber with said slide to retard the action of said spring.

4:. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and an upper section having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and oversaid crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, a hydraulic shock absorber mounted on the exterior of said upper derrick section at a place above its telescoping portion and means operatively connecting said shock absorber with said slide to retard the action of said spring.

5. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and an upper section having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, a bracket projecting outwardly from said upper derrick section at a place above its telescoping portion and a vertical drag link pivotally connecting said shock absorber with said slide to retard the action of said spring.

6. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and an upper section having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, a bracket projecting outwardly from said upper derrick section at a place above its telescoping portion and below said slide and a vertical drag link pivotally connecting said shock absorber with said slide to retard the action of said spring.

'7. A drilling machine, comprising a frame carrying a spudder mechanism, a derrick rising from said frame, a vertically movable crown sheave slide at the upperend of said derrick, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and derrick and yieldingly supporting said slide in an elevated position, an enclosed cylinder mounted on said derrick with its axis parallel with the line of movement of said slide, a piston in said cylinder and a vertical piston rod connecting said piston with said slide, said cylinder being adapted to be filled with a liquid to retard the action of said spring.

8. A drilling machine, comprising a frame carrying a spudder mechanism, a lattice Work derrick rising from said frame, a vertically movable crown sheave slide at the upper end of said derrisk, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and derrick and yieldingly supporting said slide in an elevated position, an enclosed cylinder mounted on and housed-within said lattice work derrick and coaxial'with the major axis of the derrick, a piston in said cylinder and a coaxial piston rod connecting said piston with said slide, said cylinder being adapted to be filled with a liquid to retard the action of said spring.

9. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and an upper section of latticed ladder form having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, an enclosed cylinder mounted on and housed within said lattice work upper derrick section below said slide and coaxial with the major axis of the derrick, a piston in said cylinder and a coaxial piston rod connecting said piston with said slide, said cylinder being adapted to be filled with a liquid to retard the action of said spring.

10. A drilling machine, comprising a frame carrying a spudder mechanism, a telescopic derrick including a section rising from said frame and .an upper section of latticed ladder form having its major portion telescoping into said lower derrick section, a vertically movable crown sheave slide at the upper end of said upper derrick section, a crown sheave carried by said crown sheave slide and carrying the line which extends from said spudder mechanism and over said crown sheave to the drill, a spring interposed between said crown sheave slide and upper derrick section and yieldingly supporting said slide in an elevated position, an enclosed cylinder mounted on and housed within said lattice work upper derrick section below said spring and slide and coaxial with the major axis of the derrick, a piston in said cylinder and a coaxial piston rod connecting said piston with said slide-and extending coaxially through said spring, said cylinder being adapted to be filled with a liquid to retard the action of said spring.

JOHN A. ELMES. 

